Four Republican presidential candidates ranking at the bottom of national polls squared off for their final debate of the year Tuesday night in Las Vegas. Topics focused on national security and the threat from the Islamic State group.

It's that time again. Black Friday is widely considered the opening of the holiday shopping season. Determined shoppers wake up at the crack of dawn that morning to take advantage of sales. One thing has always remained constant about Black Friday, and about the holiday season in general: toys.

Clemson, Alabama, Ohio State and Notre Dame are the top four teams in the College Football Playoff rankings for a second straight week. See why the Tigers, Crimson Tide, Buckeyes and Fighting Irish deserve to be at the top of the rankings in this Fab Four Rewind